North Korea is under many international sanctions related to its nuclear weapons and ballistic missile programs, which have made rapid progress under leader Kim Jong-un.

`North Korea’s nuclear and military programs are long-term threats, but the threat of cyberattacks from the country is real and immediate,` said Oh Il-seok, a researcher at the Institute of War.

North Korea’s cyberwarfare capabilities gained global attention in 2014 when the country was accused of attacking Sony Pictures Entertainment in response to the production of `The Interview,` a satirical film mocking Kim Jong-un.

Since then, North Korea has been blamed for a number of high-profile cyber attacks, including the theft of $81 million from the Bangladesh Central Bank and the 2017 WannaCry global ransomware attack, which affected about 300,000 computers.

North Korea denies any involvement, describing US accusations about WannaCry as `absurd`.

Students wearing Korean People’s Army (KPA) uniforms sit in front of computer screens while attending class at Mangyongdae Revolutionary School, on the outskirts of Pyongyang in 2018. Photo: AFP.

However, the US Department of Justice in February prosecuted three North Koreans for `participating in a large-scale criminal conspiracy to conduct a series of destructive cyber attacks`.

According to documents from the Office of the Director of National Intelligence, North Korea’s cyber program `poses an increasing threat of espionage, theft and attacks`.

North Korea’s cyber program dates back at least to the mid-1990s, when leader Kim Jong-il said `all wars in the coming years will be computer wars.`

`They are extremely proficient, professional and capable of performing advanced attacks,` said Scott Jarkoff of cybersecurity company CrowdStrike.

Department 121 recruits are trained in various coding languages and operating systems at special facilities such as Mirim University, said former student Jang Se-yul, who defected in 2007.

`We are taught to prepare against America’s cyber warfare capabilities,` Jang said.

Researcher Martyn Williams of the Stimson Center, USA, said cyber warfare is especially attractive to small, poor countries like North Korea, which are `superior in equipment such as aircraft, tanks and other systems.`

Most state-sponsored cyberattack groups are primarily used for espionage purposes, but experts say it is unusual for North Korea to deploy cyber capabilities for financial gain.

`Stealing is a lot faster and potentially a lot more profitable than trading, especially if you have skilled hackers,` Williams added.

The February US indictment accused three North Koreans of stealing more than $1.3 billion worth of money and cryptocurrency from financial institutions and companies.

The rise of cryptocurrencies like Bitcoin has given global hackers a new set of increasingly lucrative targets.

`This allows North Korea to easily launder money back home, beyond the control of the global banking system. Cryptocurrency is attractive because it is unregulated, borderless and relatively anonymous,` he said.